The Boeing C-97 was the Army Air Force cargo and transport version of the B-29. Between 1943 and 1950, 74 Stratofreighters were ordered, and the first flight occurred on Nov. 15, 1944. A tanker version, the KC-97, was introduced in 1950 using the flying boom refueling system, and all subsequent USAF contracts for C-97s were for tankers. In all, 890 aircraft were ordered: 74 C-97s and 816 KC-97s. After 1956, USAF KC-97s were gradually replaced by KC-135 jet tankers, but some were modified for continued use in other roles. In 1964, selected aircraft were returned to a tanker configuration as KC-97Ls, primarily for the Air National Guard, with two jet engines added to increase speed and altitude and make the tankers more compatible with high performance jet aircraft. Although the last USAF C/KC-97 was retired in 1973, examples remained in use with the AF Reserve and ANG as tankers for air-sea search and rescue aircraft. The KC-97 on display was flown to Barksdale AFB for the 8th Air Force Museum in 1980 after sitting in the DoD Salvage and Reclamation yard at Davis Monthan AFB, AZ, since 1975, when it was retired from the Utah Air National Guard. A team of five, three from the 2nd Bomb Wing and two from the 917th Wing, took a week to get it flight ready for what was to be the last flight of the KC-97, and it is marked to reflect a typical KC-97 of the 2nd Bomb Wing and those stationed at Barksdale in the 301st and 376th Bomb Wings.